[en] We have constructed a physical model to explain the tunneling current oscillations reported by Hickmott et al., for GaAs/AlGaAs heterostructures in high magnetic fields. We propose that the periodic structure observed is due to space charge which builds up in the undepleted layer when electrons enter it with energy just below the phonon emission threshold. Such electrons interact with the lattice to form polarons whose energy is pinned to the phonon energy, and thus has a very small group velocity. The polaron effect is strongly enhanced by the confinement of the electrons by the strong magnetic field. We infer from the current-voltage data that most of the tunneling current flows through a small area of the sample. The combined model gives reasonable quantitative agreement with experiment. 6 refs., 6 figs

[en] We show that many of the false alarms found in the search for binary neutron stars during the LIGO S3 science run are coincident with glitches in an auxiliary channel from the photo diode at the antisymmetric port. By studying how the glitches compare with simulated gravitational waves we were able to find a method that vetoes the false alarms while minimizing the potential for false dismissal

[en] The authors report a retrospective study aimed at the assessment of conformational radiotherapy optimized with deep-inspiration-breath-hold in an 'involved-node' irradiation of a localized supra-diaphragmatic Hodgkin disease. All patients of different ages and suffering from the Hodgkin disease at different stages had chemotherapy before radiotherapy. The treated volumes have been determined according to the 'involved-node' radiotherapy concept. Prescribed doses, doses received by the heart, coronaries and lungs, survival probability over three years are discussed. The concept appears to be efficient and not much toxic. Short communication

[en] Undoped ZnO nanoparticles (NPs) with size ∼12 nm were produced using forced hydrolysis methods using diethylene glycol (DEG) [called ZnO-I] or denatured ethanol [called ZnO-II] as the reaction solvent; both using Zn acetate dehydrate as precursor. Both samples showed weak ferromagnetic behavior at 300 K with saturation magnetization M_s = 0.077 ± 0.002 memu/g and 0.088 ± 0.013 memu/g for ZnO-I and ZnO-II samples, respectively. Fourier transform infrared (FTIR) spectra showed that ZnO-I nanocrystals had DEG fragments linked to their surface. Photoluminescence (PL) data showed a broad emission near 500 nm for ZnO-II which is absent in the ZnO-I samples, presumably due to the blocking of surface traps by the capping molecules. Intentional oxygen vacancies created in the ZnO-I NPs by annealing at 450 °C in flowing Ar gas gradually increased M_s up to 90 min and x-ray photoelectron spectra (XPS) suggested that oxygen vacancies may have a key role in the observed changes in M_s. Finally, PL spectra of ZnO showed the appearance of a blue/violet emission, attributed to Zn interstitials, whose intensity changes with annealing time, similar to the trend seen for M_s. The observed variation in the magnetization of ZnO NP with increasing Ar annealing time seems to depend on the changes in the number of Zn interstitials and oxygen vacancies

[en] The authors report the assessment of low-dose radiotherapy (two sessions of 2 Gy in two days) for the curative treatment of mucosa-associated lymphoid tissue (MALT) lymphoma of the lung. The treatment of this lymphoma is discussed in terms of surgery, chemotherapy, radiotherapy, or even simple monitoring. The authors analyse the results obtained on nine patients who have been treated this way since 2002, straight away for some of them, after surgery or chemotherapy for others. Survival rate, recurrence, evolutions and responses are discussed. Short communication

[en] Many naturally occurring microbiological and synthetic polymer systems have soft interfaces due, e.g., to the presence of polymer brushes at the surfaces. The initial interactions (before contact) in such systems are typically physical rather than chemical in origin, e.g. electrostatic or van der Waals forces. We calculate the form of the summed van der Waals interaction energies U_HS and U_SS between two bulk systems separated by a distance D, when one (U_HS) or both (U_SS) of their surfaces are soft. We find that the summed interactions diverge weakly as D →0, U_HS∼-1/D and U_SS ∼ -ln(1/D), and comment upon the applicability of these results

[en] We present a targeted search for blazar flux-correlated high-energy (${\mathrm{\epsilon <!--\; ??\; -->}}_{\mathrm{\nu <!--\; ??\; -->}}$ ≳ 1 TeV) neutrinos from six bright northern blazars, using the public database of northern hemisphere neutrinos detected during “IC40” 40-string operations of the IceCube neutrino observatory (2008 April to 2009 May). Our six targeted blazars are subjects of long-term monitoring campaigns by the VERITAS TeV γ-ray observatory. We use the publicly available VERITAS light curves to identify periods of excess and flaring emission. These predefined intervals serve as our “active temporal windows” in a search for an excess of neutrinos, relative to Poisson fluctuations of the near-isotropic atmospheric neutrino background, which dominates at these energies. After defining the parameters of an optimized search, we confirm the expected Poisson behavior with Monte Carlo simulations prior to testing for excess neutrinos in the actual data. We make two searches: one for excess neutrinos associated with the bright flares of Mrk 421 that occurred during the IC40 run, and one for excess neutrinos associated with the brightest emission periods of five other blazars (Mrk 501, 1ES 0806+524, 1ES 1218+304, 3C 66A, and W Comae), all significantly fainter than the Mrk 421 flares. We find no significant excess of neutrinos from the preselected blazar directions during the selected temporal windows. We derive 90% confidence upper limits on the number of expected flux-associated neutrinos from each search. These limits are consistent with previous point-source searches and Fermi GeV flux-correlated searches. Our upper limits are sufficiently close to the physically interesting regime that we anticipate that future analyses using already-collected data will either constrain models or yield discovery of the first blazar-associated high-energy neutrinos.

[en] Purpose: To determine whether hypnotherapy reduces anxiety and improves the quality of life in cancer patients undergoing curative radiotherapy (RT). Methods and materials: After providing written informed consent, 69 patients were randomized between standard curative RT alone (36 controls) and RT plus hypnotherapy (33 patients). Patients in the hypnotherapy group received hypnotherapy at the intake, before RT simulation, before the first RT session, and halfway between the RT course. Anxiety was evaluated by the State-Trait Anxiety Inventory DY-1 form at six points. Quality of life was measured by the Rand Medical Outcomes Study 36-item Health Survey (SF-36) at five points. Additionally, patients answered a questionnaire to evaluate their experience and the possible benefits of this research project. Results: No statistically significant difference was found in anxiety or quality of life between the hypnotherapy and control groups. However, significantly more patients in the hypnotherapy group indicated an improvement in mental (p < 0.05) and overall (p < 0.05) well-being. Conclusion: Hypnotherapy did not reduce anxiety or improve the quality of life in cancer patients undergoing curative RT. The absence of statistically significant differences between the two groups contrasts with the hypnotherapy patients' own sense of mental and overall well-being, which was significantly greater after hypnotherapy. It cannot be excluded that the extra attention by the hypnotherapist was responsible for this beneficial effect in the hypnotherapy group. An attention-only control group would be necessary to control for this effect

[en] 2015 will see the first observations of Advanced LIGO and the start of the gravitational-wave (GW) advanced-detector era. One of the most promising sources for ground- based GW detectors are binary neutron-star (BNS) coalescences. In order to use any detections for astrophysics, we must understand the capabilities of our parameter-estimation analysis. By simulating the GWs from an astrophysically motivated population of BNSs, we examine the accuracy of parameter inferences in the early advanced-detector era. We find that sky location, which is important for electromagnetic follow-up, can be determined rapidly (∼ 5 s), but that sky areas may be hundreds of square degrees. The degeneracy between component mass and spin means there is significant uncertainty for measurements of the individual masses and spins; however, the chirp mass is well measured (typically better than 0.1%). (paper)